Radio frequency (rf) power measurements in common public radio interface (cpri) sprectrum analysis

ABSTRACT

A test device for testing a power of a signal at a cell site using RFoCPRI™ is disclosed. The test device may comprise a receiver to receive a signal from a test point near a baseband unit (BBU) of a cell site. The test device may also comprise a processor to determine power of the signal. The processor may identify IQ data from the signal, determine an offset based on a noise floor determined from at least one specification of a remote radio head (RRH) of the cell site, and generate a power spectrum based on the IQ data and the offset. The processor may transmit the power spectrum to an output (e.g., display), to where the power spectrum may be representative of the power of the signal between the RRH and antennas of the cell site.

TECHNICAL FIELD

This patent application relates generally to telecommunicationsnetworks, and more specifically, to systems and methods for testingtelecommunications networks by measuring radio frequency (RF) power incommon public radio interface (CPRI) spectrum analysis of a cell site.

BACKGROUND

A modern telecommunications cell site relies on a distributedarchitecture, where a base-station transceiver subsystem (BTS), forexample, is divided into two main elements. The first is a baseband unit(BBU) that typically resides at the base or bottom of a cell tower. Thesecond is a remote radio head (RRH) that performs radio frequency (RF)functions near antennas near the top of a cell tower. Because of thisdistributed architecture, RF access is generally only available at thetop of the cell tower. Given the height of such a tower, detecting andmeasuring interference can be quite cumbersome, costly, and evendangerous.

Recent technological developments have been made to providecommunications between the BBU and the RRH. For instance, the BBU andthe RRH may communicate via a common public radio interface (CPRI). Inparticular, RF over CPRI (RFoCPRI™) technology has enabled effective RFanalysis from the base of the tower, minimizing dangerous tower climbsand associated costs and inefficiencies. A technical problem, however,is that a test instrument that analyzes a CPRI signal, for example, maynot typically report RF power, or if it does, it may not be accuratelymeasured or reported. RF power measurements are often measured usingother test devices, and these test devices may not be entirely reliableas well. As a result, a technique that measures RF power using CPRIspectrum analysis may be helpful to increase network testingefficiencies and overcome shortcomings of conventional technologies.

BRIEF DESCRIPTION OF DRAWINGS

Features of the present disclosure are illustrated by way of example andnot limited in the following Figure(s), in which like numerals indicatelike elements, in which:

FIG. 1 illustrates a distributed cell site with a test instrument thatperforms common public radio interface (CPRI) spectrum analysis,according to an example;

FIG. 2 illustrate a test instrument for measuring RF power using commonpublic radio interface (CPRI) spectrum analysis, according to anexample;

FIG. 3A illustrates common public radio interface (CPRI) multiplexingwith test points, according to an example;

FIG. 3B illustrates a common public radio interface (CPRI) protocol,according to an example;

FIG. 3C illustrates IQ data represented in polar form for measuring RFpower using common public radio interface (CPRI) spectrum analysis,according to an example;

FIG. 3D illustrates a frame structure for an IQ data block measuring RFpower using common public radio interface (CPRI) spectrum analysis,according to an example;

FIG. 4 illustrates a distributed cell site with a test instrument formeasuring RF power using common public radio interface (CPRI) spectrumanalysis, according to an example; and

FIG. 5 illustrates a flow chart of a method for measuring RF power usingcommon public radio interface (CPRI) spectrum analysis, according to anexample.

DETAILED DESCRIPTION

For simplicity and illustrative purposes, the present disclosure isdescribed by referring mainly to examples and embodiments thereof. Inthe following description, numerous specific details are set forth inorder to provide a thorough understanding of the present disclosure. Itwill be readily apparent, however, that the present disclosure may bepracticed without limitation to these specific details. In otherinstances, some methods and structures readily understood by one ofordinary skill in the art have not been described in detail so as not tounnecessarily obscure the present disclosure. As used herein, the terms“a” and “an” are intended to denote at least one of a particularelement, the term “includes” means includes but not limited to, the term“including” means including but not limited to, and the term “based on”means based at least in part on.

As described above, a distributed cell site may have a baseband unit(BBU) that resides at the base or bottom of a cell tower and a remoteradio head (RRH) that performs radio frequency (RF) functions locatednear antennas at the top of the cell tower. Modern cell architecture hasalso replaced coax-based feeders with fiber-based ones to connect theBBU and RRH. This change has reduced problems associated with signalloss and reflections. However, since RF interfaces reside on the RRH,most RF maintenance, troubleshooting, or measurements still requiresaccess at the top of a cell tower. Tower climbs and access to the RRHmay burdensome, inefficient, and even hazardous.

Recent advancements in technology have made it possible for the BBU andthe RRH to communicate via a common public radio interface (CPRI). Inparticular, RF over CPRI (RFoCPRI™) technology has enabled effective RFanalysis from the base of the tower, minimizing dangerous tower climbsand associated costs and inefficiencies. However, a test instrument thatanalyzes a CPRI signal, for example, may not generally report RF power,or if it does, such reports may not be accurate or reliable.Furthermore, RF power measurements are often measured by using othertest devices. Not only is this cumbersome for any network operator ortechnician, but these separate test devices may not be entirely reliableas well. Accordingly, techniques for measuring RF power using a testdevice that performs CPRI spectrum analysis are disclosed herein.

FIG. 1 illustrates a distributed cell site 100 with a test instrumentthat performs CPRI spectrum analysis, according to an example. As shown,a cell site 100 may be a tower with one or more antennas 101 near thetop of a cell tower. The cell site 100 may be a distributed cell sitehaving at least one remote radio head (RRH) 103 that performs radiofrequency (RF) functions. The RRH 103 may be located near antennas 101at the top of the cell tower. The cell site 100 may also have at leastone baseband unit (BBU) 105 that resides at the base or bottom of thecell tower. An optical fiber 107 (or fiber-based or optical feeder) mayconnect the BBU 105 and the RRH 103. The BBU 105 may be connected to abackhaul 109, which may include base station controllers or othercomponents that provide network connectivity standard totelecommunications industries. A test instrument 200 may measure signalsat the cell site 100 at various test points.

The RRH 103 may include various components and circuitry. For example,the RRH 103 may include radio equipment (RE) having various RFcircuitry, such as converters, filters, oscillators, amplifiers,modulators, etc. These components may allow the RRH to covert opticalsignals to electrical signals, and vice versa. This may be particularlyuseful in CPRI. Other features of the RRH 103 may includereceiving/transmitting a desired band of signals from/to antennas,amplifying signals to desired power levels, filtering signals,converting signals, or other related actions.

The BBU 105 may a unit that processes baseband at call sites fortelecommunications systems. Baseband may refer a signal that has a verynarrow and near-zero frequency range, e.g., low-pass or non-modulatedsignal. The BBU 105 may include, among other things, radio equipmentcontrol (REC) which is responsible for communication through thephysical interface. The BBU 105 may be connected to a backhaul 109,which in turn may be connected to a core telecommunications network.Backhaul 109 may be standard industry technologies, such as free-spaceoptical, microwave relay, Ethernet, WiMAX, SONET, DSL, or other similartechnologies.

FIG. 2 illustrates a block diagram of a test instrument 200 formeasuring RF power using common public radio interface (CPRI) spectrumanalysis, according to an example. The test instrument 200 may includeone or more ports 203 for connecting the test instrument 200 to a testpoint, such as the test point 309A shown in FIG. 3A. The ports 203 mayinclude connectors for connecting to cables at a cell site carryingtraffic for upstream and downstream channels. The test instrument 200may include a telemetry interface 204 for connecting to a telemetrychannel, such as a WiFi interface, Bluetooth interface, cellularinterface or another network interface. The test instrument 200 may alsoconnect to a remote device via the telemetry interface 204.

The test instrument 200 may include one or more ports 203 to connect tovarious test points at the cell site, such as the front haul of the BBU105. In an example, the port(s) may include coaxial or optical RF cableconnectors. It will be appreciated that test instrument 200 may alsohave other non-cable ports, for example, to connect to a computer or toan external display, such as, but not exclusively, one or more USB portsand the like.

The test instrument 200 may include a user interface which may include akeypad 205 and display 213. The display 213 may include a touch screendisplay. A user may interact with the test instrument 200 via the userinterface to enter information, select operations, view measurements,examine signal profiles, communicate with other devices, etc.

A data storage 251 may store any information used by the test instrument200 and may include memory or another type of known data storage device.The data storage 251 may store power measurements and/or any othermeasurements or data used by the test instrument 200. The data storage251 may include a non-transitory computer readable medium storingmachine-readable instructions executable by processing circuit 250 toperform operations of the test instrument 200.

A transmission circuit 241 may include a circuit for sending testsignals into the cell site to perform various tests. The transmissioncircuit 241 may include encoders, modulators, and other known componentfor transmitting signals in the network. A receiver circuit 242 mayinclude components for receiving signals from the network. Thetransmission circuit 241 and/or the receiver circuit 242 may alsoinclude other components, such as a demodulator, a decoder, an ADC,and/or other circuit components or elements.

A processing circuit 250 may include any suitable hardware to performthe operations of the test instrument 200 described herein, includingthe operations described with respect to FIGS. 3-5 and the techniquesdescribed herein, or otherwise. For example, the operations may includemeasuring and testing operations. The processing circuit 250 may includeother components as well, such as a signal/interference analyzer,spectrum analyzer, profile/spectrum generator, and other measurement andreporting components. The hardware of the test instrument 200, includingthe processing circuit 250, may include a hardware processor,microcontroller, a digital signal processor (DSP), an applicationspecific integrated circuit (ASIC), a field programmable gate array(FPGA) or other programmable logic device, discrete gate or transistorlogic, discrete hardware components, or any combination thereof designedto perform the functions and methods described herein. In an example,one or more of the functions and operations of the test instrument 200described herein may be performed by the processing circuit 250 or otherhardware executing machine readable instructions stored in anon-transitory computer readable medium, which may comprise RAM (randomaccess memory), ROM (read only memory), EPROM (erasable, programmableROM), EEPROM (electrically erasable, programmable ROM), hard drives,flash memory, or other types of storage devices, which may be volatileand/or nonvolatile. It should be appreciated that the test instrument200 may include components other than what is shown.

A cooperative industry effort defined as CPRI may be a specification foran interface between a radio equipment control (REC) (e.g., located ator near the BBH 105) and a radio equipment (RE) (e.g., located at ornear the RRH 103). In some examples, CPRI may the specification forinterfacing an REC and RE when optical fiber (or fiber-optic feeder) isdeployed.

FIG. 3A illustrates common public radio interface (CPRI) multiplexing300A, according to an example. As shown, radio equipment (RE) 303 may beconnected to antennas 101 for over-air interface. The RE 303 may beconnected to radio equipment control (REC) 305 via an optical fiber(e.g., CPRI 307). The REC 305 may be connected to backhaul 109 fornetwork interface.

The CPRI interface may be characterized by a full-duplex, synchronized,and steady transfer of digital baseband data that guarantees highbandwidth and high throughput with low latency. Less time-critical data,such as control information (e.g., for link setup), as well astime-aligned data (e.g., for Rx and Tx gain control) may be transferredin addition to user information.

As depicted, three different information flows may be multiplexed overCPRI. These may include: (i) user-plane data, (ii) control- andmanagement-plane data, and (iii) synchronization-plane data. The clockand timing control may ensure that the REC 305 and RE 303 aresynchronized. Timing information may be included in baseband data. Aframe structure with control words (CWs) may provide a basis fortransfer of that information. The RE 303 may synchronize its clock andframe timing to a master reference (clock recovery) at the REC 305. Thismay be essential to map/demap or code/decode digital data correctly aswell as to resend CPRI data to another RRH in a chain topology.

Referring back to FIG. 1, the test instrument 200 may test and measuresignals at various test points at the cell site. In an example, as shownin FIG. 3, the test instrument 200 may measure and analyze signals fromtest point 309A, a point along the optical fiber 107 (or CPRI 307 inFIG. 3) at a front haul area near the REC 305. Taking advantage ofRFoCPRI technology, the test instrument 200 may measure and analyzesignals at an uplink (UL) of the optical fiber 107. In this way, eventhough the operator or technician may be at test point 309A near theBBU, he or she may be effectively measuring the signal between theantenna and RRH at test point 309B, without having to climb the tower ofthe cell site. It should be appreciated that while techniques describedherein are directed to power measurements, RFoCPRI spectrum analysis mayprovide a host of measurements, including various RF metrics, such asDTF, VSWR, as well as optical power, integrity, performance, etc.

FIG. 3B illustrates a common public radio interface (CPRI) protocol300B, according to an example. The CPRI protocol 300B may define Layer 1(PHY) and Layer 2 (MAC) of the Open System Interconnection (OSI) model.Higher layers may not be specified by CPRI but defined and implementedby vendors of the REC and RE. In other words, there are manypossibilities for using CPRI data containers for individual users, aswell as control and management information. The user (baseband IQ),control and management, and synchronization data streams may bemultiplexed over the same physical interface. In this example, Layer 1may include electrical transmission and/or optical transmission, as welltime division multiplexing (TDM). Layer 2 may include information flowsthat involve IQ data, vendor specific, Ethernet, HDLC, and/or L1 in-bandprotocol.

FIG. 3C illustrates IQ data represented in polar form for measuring RFpower using common public radio interface (CPRI) spectrum analysis 300C,according to an example. It should be appreciated that RF communicationsystems use advanced forms of modulation to increase the amount of datathat can be transmitted in a given amount of frequency spectrum. Signalmodulation may be divided into two broad categories: analog modulationand digital modulation. IQ data may then be understood as a translationof amplitude and phase data from a polar coordinate system to aCartesian (X, Y) coordinate system. As shown in FIG. 3C, usingtrigonometry, polar coordinate sine wave information may be convertedinto Cartesian I/Q sine wave data. These two representations may beequivalent and contain the same information, just in different forms.

Accordingly, IQ data may represent a message signal, and projectionsonto the I and Q axes may represent individual I and Q waveformscorresponding to a PM sine wave with fixed magnitude and oscillatingphase. Because the IQ data waveforms are Cartesian translations of polaramplitude and phase waveforms, additional analysis may be needed todetermine a nature or content of the message signal. Such analysis mayhelp measure power, interference, signal performance, etc. of themessage signal.

FIG. 3D illustrates a frame structure for an IQ data block measuring RFpower using common public radio interface (CPRI) spectrum analysis 300D,according to an example. An IQ data block structure for a 1,228.8 Mb/sCPRI line bit rate may be shown in 300D. IQ data may be transferred inthe form of a frame structure with basic, hyper, and radio frames. Abasic frame may consist of 16 words. The first word (W0) of each framemay be a CW. The remaining words (W1-15) may be used for user IQ data(IQ data block).

As described above, an operator or technician may perform spectrumanalysis on an uplink (UL) to find out if there are any issues presentover the air. This would typically occur at a test point betweenantennas 101 and the RRH 103, as shown in FIG. 1. However, there aremany challenges to do this and techniques described herein, usingRFoCPRI technology, may help obviate these obstacles.

FIG. 4 illustrates a distributed cell site with a test instrument formeasuring RF power using common public radio interface (CPRI) spectrumanalysis, according to an example. As shown, the test instrument 200 maybe connected at a test point near a front haul of the BBU 105. Morespecifically, the test instrument 200 may monitor CPRI uplink (fromRRH). While examples described herein are directed to monitoring ULchannels, it should be appreciated that test instrument 200 may alsomonitor downlink (from BBU) signals as well.

In general, the test instrument 200 may use RFoCPRI to perform a varietyof RF maintenance, troubleshooting, and performance operations at aground level via optical fiber 107 at a front haul of the BBU 105. Forinstance, the test instrument 200 may use RFoCPRI to verify CPRI controlsignals and may also extract RF (IQ) data transmitted between the BBUand RRU. This may enable monitoring and analysis of interference ofmobile terminals (uplink), as well as the radio's signal analysis(uplink/downlink).

As described above, there are no systems that accurately report RF powerby simply analyzing CPRI signal. At best, conventional spectralanalyzers may measure power in resolution bandwidth (RBW). This,however, may need to be correlated as noise floor in LTE 180 KHz RB(resource block) to determine power of an RF signal in CPRI. The noisefloor may be an RF noise floor. In this way, the test instrument 200 mayemploy spectral analysis using CPRI protocol 300B to determine RF powerof the signal as if the test instrument were at a test point between theRRH 103 and antennas 101. The test instrument 200 may also use thisspectral analysis to generate a variety of reports and analyses 410 foran operator or technician.

FIG. 5 illustrates a flow chart of a method 500 for measuring RF powerusing common public radio interface (CPRI) spectrum analysis, accordingto an example. The method 500 is provided by way of example, as theremay be a variety of ways to carry out the method described herein.Although the method 500 is primarily described as being performed bytest instrument 200 in at least scenarios depicted in FIGS. 1-4, themethod 500 may be executed or otherwise performed by one or moreprocessing components of the test instrument 200, or by another systemor a combination of systems. Each block shown in FIG. 5 may furtherrepresent one or more processes, methods, or subroutines, and one ormore of the blocks may include machine readable instructions stored on anon-transitory computer readable medium and executed by a processor orother type of processing circuit to perform one or more operationsdescribed herein.

At block 501, the test instrument 200 may receive, at the port 203,receiver circuit 242, and/or processing circuit 250, a signal from atest point at a cell site. The cell site may be a distributed cell sitesuch that a remote radio head (RRH) 103 and a baseband unit (BBU) 105are separated and connected via an optical fiber 107 (or feeder). In anexample, the signal may be a radio frequency (RF) over common publicradio interface (CPRI) (RFoCPRI) signal. For RF power measurement, thetest point 309A be at a front haul of the baseband unit (BBU).

At block 503, the processing circuit 250 of the test instrument 200 mayreceive or identify IQ data from the signal. As described above, IQ datamay include information associated with power of the signal. The powerof the signal may be radio frequency (RF) power. Using this information,in addition to various operations or techniques, the test instrument 200may then determine, at the processing circuit 250, a more accurate andreliable power measurement of the signal.

At block 503, the test instrument 200 may determine, at the processingcircuit 250, an offset based on a noise floor and a specification of aremote radio head (RRH) 103 from which the signal is traversing. Thespecification of the RRH 103, for example, may be tied to a brand, amodel number, a design, an arrangement of components in the RRH 103, orother particular detail. The arrangement of components that affect theoffset determination may include an amplifier, a band pass filter, avoltage-controlled oscillator (VCO), a modulator, or other component. Inother words, in order to provide an accurate power measurement, it willbe important to know what type of RRH is employed at the top of thetower. For example, if an ALU® PRB (power resource block) or Ericsson®RB (resource block) is used—each with its own specific designs,components, and layouts, this detail may be used to determine theappropriate offset and noise floor.

Other than having these specifications stored in the test instrument200, it should be appreciated that there may other techniques that couldbe used to help determine the offset. For example, an operator or usermay be able to manual enter parameters into the test instrument 200 tohelp determine the offset. In another example, the test instrument maysend a test signal and, using known parameters, determine the offsetthat way. In yet another example, the test instrument 200 may use thetelemetry interface to search third party data sources for thespecification information that is not already pre-stored or manuallyentered into the test instrument 200. These and other techniques may beprovided to facilitate offset determinations.

At block 504, the test instrument 200 may generate, at the processingcircuit 250, a power spectrum based on the IQ data and offset. It shouldbe appreciated that the power spectrum be generated in a variety ofways. In an example, an initial (first) power spectrum may first begenerated based on the IQ data. The offset may then be applied tonormalize the initial power spectrum. A second (final) power spectrummay then be generated based on the normalization of the initial powerspectrum. It should be appreciated that other techniques may be used.For example, an initial power spectrum may not be generated at all. Theoffset may be applied values and parameters of the power signaldirectly. In this case, the only spectrum generated would be the finalpower spectrum.

At block 505, the test instrument 200 may transmit, at the processingcircuit 250, the power spectrum to an output. The output may be adisplay that provides at visual data, audio data, textual dataassociated with the power of the signal to be viewed by an operator oruser of the test instrument. As disclosed herein, the power spectrumthat is outputted may be representative of the power of the signalbetween the RRH 103 and antennas 101 of the cell site, even though thesignal is received at a test point near the BBU 105.

It should also be appreciated that the test instrument 200 may alsoprovide other components not shown. For example, middleware (not shown)may be included as well. The middleware may include software hosted byone or more servers or devices. Furthermore, it should be appreciatedthat some of the middleware or servers may or may not be needed toachieve functionality. Other types of servers, middleware, systems,platforms, and applications not shown may also be provided at theback-end to facilitate the features and functionalities of the testingand measurement system.

Moreover, single components may be provided as multiple components, andvice versa, to perform the functions and features described herein. Itshould be appreciated that the components of the system described hereinmay operate in partial or full capacity, or it may be removed entirely.It should also be appreciated that analytics and processing techniquesdescribed herein with respect to the test instrument 200, for example,may also be performed partially or in full by other various componentsof the overall system.

It should be appreciated that the data stores described herein mayinclude volatile and/or nonvolatile data storage that may store data andsoftware or firmware including machine-readable instructions. Thesoftware or firmware may include subroutines or applications thatperform the functions of the test instrument 200 and/or run one or moreapplication that utilize data from the test instrument 200 or othercommunicatively coupled system.

The various components, circuits, elements, and interfaces, may be anynumber of hardware, network, or software components, circuits, elements,and interfaces that serves to facilitate communication, exchange, andanalysis data between any number of or combination of equipment,protocol layers, or applications. For example, the interfaces describedherein may each include a network interface to communicate with otherservers, devices, components or network elements via a network.

Although examples are directed to measuring radio frequency (RF) powerin common public radio interface (CPRI) spectrum analysis of a cellsite, it should be appreciated that that the test instrument 200 mayalso use these and other various techniques in to provide interferenceanalysis, signal analysis, and/or other related RF measurements.Ultimately, the systems and methods described herein may minimize celltowner climbs and improve safety, reduce number of testing devices,increase accuracy and reliability, and significantly reduce maintenanceand operation expenses.

What has been described and illustrated herein are examples of thedisclosure along with some variations. The terms, descriptions, andfigures used herein are set forth by way of illustration only and arenot meant as limitations. Many variations are possible within the scopeof the disclosure, which is intended to be defined by the followingclaims—and their equivalents—in which all terms are meant in theirbroadest reasonable sense unless otherwise indicated.

1-21. (canceled)
 22. A test device, comprising: a processor to determinepower of a signal from a test point of a cell site by: receiving datafrom the signal, where in the data comprises information associated withpower of the signal; determining an offset based on a noise floor and atleast one specification of a remote radio head (RRH) from which thesignal is traversing; and generating a power spectrum based on the dataand offset, wherein the power spectrum is representative of the power ofthe signal between the RRH and antennas of the cell site.
 23. The testdevice of claim 22, wherein the signal is a radio frequency (RF) overcommon public radio interface (CPRI) (RFoCPRI) signal.
 24. The testdevice of claim 22, wherein the power of the signal is a radio frequency(RF) power.
 25. The test device of claim 22, wherein the cell site is adistributed cell site such that the remote radio head (RRH) and abaseband unit (BBU) are separated and connected via an optical feeder.26. The test device of claim 25, wherein the test point is at a fronthaul of the baseband unit (BBU) or near the BBU of the cell site. 27.The test device of claim 26, wherein the offset normalizes to the powerspectrum such that the power spectrum, even though measured at a fronthaul of the baseband unit (BBU), represents power between the RRH andantennas.
 28. The test device of claim 22, wherein the specification ofthe RRH comprises a brand, a model number, a design, or an arrangementof components, wherein the arrangement of components comprises at leastone of an amplifier, a band pass filter, a voltage-controlled oscillator(VCO), or a modulator.
 29. The test device of claim 22, whereingenerating the power spectrum comprises: generating an initial powerspectrum based on the data; applying the offset to normalize the initialpower spectrum; and generating the power spectrum based on thenormalization.
 30. The test device of claim 22, wherein the processorfurther comprises: transmitting the power spectrum to an output, whereinthe output is a display that provides at least one of visual data oraudio associated with the power of the signal to a user.
 31. A method,comprising: receiving a signal from a test point of a cell site;identifying data from the signal, wherein the data comprises informationassociated with power of the signal; determining an offset based on anoise floor and at least one specification of a remote radio head (RRH)from which the signal is traversing; and generating a power spectrumbased on the data and offset, wherein the power spectrum isrepresentative of the power of the signal between the RRH and antennasof the cell site.
 32. The method of claim 31, wherein the signal is aradio frequency (RF) over common public radio interface (CPRI) (RFoCPRI)signal.
 33. The method of claim 31, wherein the power of the signal is aradio frequency (RF) power.
 34. The method of claim 31, wherein the cellsite is a distributed cell site such that the remote radio head (RRH)and a baseband unit (BBU) are separated and connected via an opticalfeeder.
 35. The method of claim 34, wherein the test point is at a fronthaul of the baseband unit (BBU) or near the BBU of the cell site. 36.The method of claim 35, wherein the offset normalizes to the powerspectrum such that the power spectrum, even though measured at a fronthaul of the baseband unit (BBU), represents power between the RRH andantennas.
 37. The method of claim 31, wherein the specification of theRRH comprises a brand, a model number, a design, or an arrangement ofcomponents, wherein the arrangement of components comprises at least oneof an amplifier, a band pass filter, a voltage-controlled oscillator(VCO), or a modulator.
 38. The method of claim 31, wherein generatingthe power spectrum comprises: generating an initial power spectrum basedon the data; applying the offset to normalize the initial powerspectrum; and generating the power spectrum based on the normalization.39. The method of claim 31, further comprising: transmitting the powerspectrum to an output, wherein the output is a display that provides atleast one of visual data or audio associated with the power of thesignal to a user.
 40. A non-transitory computer-readable storage mediumhaving an executable stored thereon, which when executed instructs aprocessor to: receive a signal from a test point of a cell site;identify data from the signal, wherein the data comprises informationassociated with power of the signal; determine an offset based on anoise floor and at least one specification of a remote radio head (RRH)from which the signal is traversing; and generate a power spectrum basedon the data and offset, wherein the power spectrum is representative ofthe power of the signal between the RRH and antennas of the cell site.41. The non-transitory computer-readable storage medium of claim 40,further comprising: transmitting the power spectrum to an output,wherein the output provides at least one of visual data or audioassociated with the power of the signal to a user.